Re: [PATCH] t0213: skip ancestry tests under user-mode emulation

On Mon, Jul 06, 2026 at 05:34:01PM +0000, Jamie Magee via GitGitGadget wrote:
> From: Jamie Magee <[email protected]>
> 
> The tests added in 3c8c638df6 (t0213: add trace2 cmd_ancestry tests,
> 2026-02-13) expect the cmd_ancestry event to name "test-tool" and
> "git". On Linux those names come from the "comm" field of
> /proc/<pid>/stat. Under user-mode emulation (e.g. qemu-user) /proc
> reports the emulator ("qemu-riscv64") instead, so the event is still
> emitted, the TRACE2_ANCESTRY probe enables the tests, and tests 2-5
> fail even though they pass on native riscv64.
> 
> Require the probe to see "test-tool" in the ancestry of a test-tool
> spawned from test-tool, so the tests skip when the names are unreliable.
> 
> Cc: Matthew John Cheetham <[email protected]>
> Signed-off-by: Jamie Magee <[email protected]>
> ---

Very sorry to say something completely outside the patch.

But may I ask what's the point of writting the line started with "Cc:"?
I know that Linux kernel has something about writting Cc in the commit
message, while I don't see much from Git's documentation about trailers,
including MyFirstContribution and SubmittingPatches. Although I know
that "git send-email" and "git interpret-trailers" could use "Cc:", I
still wonder whether using this trailer is encouraged or not. If so,
adding some decriptions about it would be nice, I guess, since I was
confused when reading kernel docs about using Cc trailers in the commit
message sometime ago.

Sorry in advance if I missed any context.

Thanks very much.